Which factors may determine the vulnerability of a GWPA?

The vulnerability of a Groundwater Protection Area (GWPA) is influenced by specific environmental and geological factors that can affect the likelihood of contamination or degradation of the groundwater quality. Soil type is fundamental because different soil textures and compositions can either filter or allow contaminants to percolate through more easily. For instance, sandy soils typically have higher permeability, which can lead to greater movement of pollutants into the groundwater.

Climate also plays a crucial role, as it influences precipitation patterns and evaporation rates, affecting how water moves through the soil and the recharge rates of groundwater systems. Additionally, the depth to groundwater is critical; shallower groundwater may be more susceptible to surface contaminants, as there is less soil to act as a natural filter.

Therefore, considering these elements—soil type, climate variations, and groundwater depth—provides a comprehensive understanding of how susceptible a groundwater resource may be to various pollutants and disturbances. This highlights the interconnectedness of geological and environmental characteristics in determining a GWPA's vulnerability, making option A the most appropriate choice.